Pence told the military members that he had spoken twice with President Donald Trump during the day. US military officials have said the USA doesn't intend to use force in response to either a nuclear test or a missile launch by the North. Kim's No. 2 official accused Trump of "creating a war situation" and said the North "will respond to an all-out war with an all-out war and a nuclear war with our style of a nuclear attack".
A North Korean missile "blew up nearly immediately" on its test launch on Sunday, the U.S. Pacific Command said, hours before U.S. Vice President Mike Pence was due in South Korea for talks on the North's increasingly defiant arms programme. China has backed North Korea since the peninsula was last at war in the 1950s, in part to prevent having an American ally on its border. A second USA official said the launch was land-based.
"At present, we are in close contact with the United States and South Korea and in addition to urging (the North) to refrain from provocative actions and observe relevant UN Security Council resolutions, we will take all necessary steps to protect our people's lives and assets", Suga said.
Sinpo, where the Sunday launch took place, is the site of a North Korean submarine base and where the North has tested the submarine-launched ballistic missile it is developing.
A US strike may prompt North Korea to immediately unleash artillery fire on Seoul and its surroundings, which is home to just more than half of South Korea's 51 million people, according to a report published by Stratfor previous year.
Ahead of Pence's arrival, North Korea's vice foreign minister told The Associated Press in an interview that Trump was the culprit of escalating tensions through his tweets and expansion of military exercises, arguing that the US was becoming "more vicious and more aggressive" under Trump compared to his predecessor. He said Pence will try to balance reassurance with a willingness to respond if North Korea acts.
The U.S. Pacific Command said in a statement that Sunday's missile exploded on launch.
The Yomiuri Shimbun North Korea made clear its defiant stance toward the United States by displaying its military capabilities.
With the country said to be preparing another nuclear test, the US Navy have moved a strike group within range of the Korean peninsula.
The extended-range Scud missile in that earlier launch suffered an in-flight failure and fell into the sea off North Korea's east coast, according to USA imagery and assessments.
Pence said North Korea's "provocation" was another reminder of the risks that US and South Korean service members face every day "in the defense of the freedom of the people of South Korea and the defense of America in this part of the world".
Details are still scant on what sort of missile this latest test launch was.
Washington sees North Korea's pursuit of nuclear weapons and ballistic missiles as a threat to world security and to its Asian allies, Japan and South Korea.
The Chinese government announced in February it would ban coal imports from North Korea until the end of the year.
Six-nation negotiations on dismantling North Korea's nuclear program in exchange for aid fell apart in early 2009.